document.write( "Question 948400: How would I find the x and y-intercept and vertex of: H(x)=3x-1/2x^2\r
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Algebra.Com's Answer #578886 by macston(5194)\"\" \"About 
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H(x)=3x-1/2x^2 Write the equation in the form:
\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"
\n" ); document.write( "In this case:
\n" ); document.write( "\"%28-1%2F2%29x%5E2%2B3x=y\"
\n" ); document.write( " The x-intercept is where y=0 so
\n" ); document.write( "\"%28-1%2F2%29x%5E2%2B3x%2B0=0\"\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-0.5x%5E2%2B3x%2B0+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%283%29%5E2-4%2A-0.5%2A0=9\".
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\n" ); document.write( " Discriminant d=9 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-3%2B-sqrt%28+9+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%283%29%2Bsqrt%28+9+%29%29%2F2%5C-0.5+=+0\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%283%29-sqrt%28+9+%29%29%2F2%5C-0.5+=+6\"
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\n" ); document.write( " Quadratic expression \"-0.5x%5E2%2B3x%2B0\" can be factored:
\n" ); document.write( " \"-0.5x%5E2%2B3x%2B0+=+-0.5%28x-0%29%2A%28x-6%29\"
\n" ); document.write( " Again, the answer is: 0, 6.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-0.5%2Ax%5E2%2B3%2Ax%2B0+%29\"

\n" ); document.write( "\n" ); document.write( "The answers are 0 and 6, so the x-intercepts are (0,0) and (6,0)
\n" ); document.write( "And the y-intercept(s) is where x=0, so:
\n" ); document.write( "\"y=%28-1%2F2%290%5E2%2B3%280%29\"
\n" ); document.write( "y=0 So the y-intercept is at the origin (0,0)
\n" ); document.write( "The axis of symmetry is given by: (This is the x value of the vertex)
\n" ); document.write( "\"x=-b%2F2a\"
\n" ); document.write( "In this case:
\n" ); document.write( "\"x=%28-3%29%2F%282%28-1%2F2%29%29\"
\n" ); document.write( "x=3 Substitute this in the original equation to get the y value of the vertex.
\n" ); document.write( "\"y=%28-1%2F2%293%5E2%2B3%283%29\"
\n" ); document.write( "\"y=%28-1%2F2%29%289%29%2B9\"
\n" ); document.write( "\"y=-4.5%2B9\"
\n" ); document.write( "y=4.5 So the vertex is (3,4.5)\r
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